package com.sharemob.tinchat.lib;

import android.graphics.Bitmap;

public class BitmapUtil {
   
       /**
        * 创建一个虚化的位图
        * @param sentBitmap 原位图
       * @param radius 虚化半径
       * @return 虚化后的位图
       */
      public static Bitmap createBlurBitmap(Bitmap sentBitmap, int radius) {
          Bitmap bitmap = sentBitmap.copy(sentBitmap.getConfig(), true);
          if (radius < 1) {
              return (null);
          }
          int w = bitmap.getWidth();
          int h = bitmap.getHeight();
          int[] pix = new int[w * h];
          bitmap.getPixels(pix, 0, w, 0, 0, w, h);
          int wm = w - 1;
         int hm = h - 1;
          int wh = w * h;
          int div = radius + radius + 1;
          int r[] = new int[wh];
         int g[] = new int[wh];
          int b[] = new int[wh];
         int rsum, gsum, bsum, x, y, i, p, yp, yi, yw;
          int vmin[] = new int[Math.max(w, h)];
          int divsum = (div + 1) >> 1;
          divsum *= divsum;
         int dv[] = new int[256 * divsum];
         for (i = 0; i < 256 * divsum; i++) {
              dv[i] = (i / divsum);
          }
          yw = yi = 0;
          int[][] stack = new int[div][3];
          int stackpointer;
          int stackstart;
          int[] sir;
          int rbs;
          int r1 = radius + 1;
          int routsum, goutsum, boutsum;
          int rinsum, ginsum, binsum;
          for (y = 0; y < h; y++) {
              rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;
              for (i = -radius; i <= radius; i++) {
                  p = pix[yi + Math.min(wm, Math.max(i, 0))];
                  sir = stack[i + radius];
                  sir[0] = (p & 0xff0000) >> 16;
                  sir[1] = (p & 0x00ff00) >> 8;
                  sir[2] = (p & 0x0000ff);
                  rbs = r1 - Math.abs(i);
                  rsum += sir[0] * rbs;
                  gsum += sir[1] * rbs;
                  bsum += sir[2] * rbs;
                  if (i > 0) {
                      rinsum += sir[0];
                     ginsum += sir[1];
                      binsum += sir[2];
                  } else {
                      routsum += sir[0];
                      goutsum += sir[1];
                      boutsum += sir[2];
                  }
              }
              stackpointer = radius;
              for (x = 0; x < w; x++) {
                  r[yi] = dv[rsum];
                  g[yi] = dv[gsum];
                  b[yi] = dv[bsum];
                  rsum -= routsum;
                  gsum -= goutsum;
                  bsum -= boutsum;
                  stackstart = stackpointer - radius + div;
                  sir = stack[stackstart % div];
                  routsum -= sir[0];
                  goutsum -= sir[1];
                  boutsum -= sir[2];
                  if (y == 0) {
                      vmin[x] = Math.min(x + radius + 1, wm);
                  }
                  p = pix[yw + vmin[x]];
                  sir[0] = (p & 0xff0000) >> 16;
                  sir[1] = (p & 0x00ff00) >> 8;
                  sir[2] = (p & 0x0000ff);
                  rinsum += sir[0];
                  ginsum += sir[1];
                  binsum += sir[2];
                  rsum += rinsum;
                  gsum += ginsum;
                bsum += binsum;
                 stackpointer = (stackpointer + 1) % div;
                sir = stack[(stackpointer) % div];
                 routsum += sir[0];
                 goutsum += sir[1];
                 boutsum += sir[2];
                rinsum -= sir[0];
                 ginsum -= sir[1];
                 binsum -= sir[2];
                 yi++;
            }
             yw += w;
         }
        for (x = 0; x < w; x++) {
            rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;
             yp = -radius * w;
             for (i = -radius; i <= radius; i++) {
                yi = Math.max(0, yp) + x;
                sir = stack[i + radius];
                 sir[0] = r[yi];
                 sir[1] = g[yi];
                 sir[2] = b[yi];
                rbs = r1 - Math.abs(i);
                 rsum += r[yi] * rbs;
                gsum += g[yi] * rbs;
                bsum += b[yi] * rbs;
                 if (i > 0) {
                     rinsum += sir[0];
                    ginsum += sir[1];
                    binsum += sir[2];
                } else {
                    routsum += sir[0];
                    goutsum += sir[1];
                     boutsum += sir[2];
                 }
                if (i < hm) {
                     yp += w;
                 }
             }
            yi = x;
             stackpointer = radius;
            for (y = 0; y < h; y++) {
                pix[yi] = ( 0xff000000 & pix[yi] ) | ( dv[rsum] << 16 ) | ( dv[gsum] << 8 ) | dv[bsum];
                 rsum -= routsum;
               gsum -= goutsum;
                bsum -= boutsum;
                stackstart = stackpointer - radius + div;
                 sir = stack[stackstart % div];
                routsum -= sir[0];
                 goutsum -= sir[1];
                 boutsum -= sir[2];
              if (x == 0) {
                    vmin[y] = Math.min(y + r1, hm) * w;
                 }
                 p = x + vmin[y];
                sir[0] = r[p];
                 sir[1] = g[p];
                 sir[2] = b[p];
                 rinsum += sir[0];
                 ginsum += sir[1];
                binsum += sir[2];
                 rsum += rinsum;
                 gsum += ginsum;
                bsum += binsum;
                 stackpointer = (stackpointer + 1) % div;
                 sir = stack[stackpointer];
                 routsum += sir[0];
                goutsum += sir[1];
                 boutsum += sir[2];
                 rinsum -= sir[0];
                 ginsum -= sir[1];
                binsum -= sir[2];
                 yi += w;
             }
         }
         bitmap.setPixels(pix, 0, w, 0, 0, w, h);
         return (bitmap);
     }
 }